export const usePageScrollOpacity = (scrollTop, start_range = 20, end_range = 100) => {
	let opacityNum = 0
	if (scrollTop >= 0) {
		if (scrollTop <= start_range) opacityNum = 0
		else if (start_range < scrollTop && scrollTop <= end_range) opacityNum = scrollTop / 100
		else if (scrollTop > end_range) opacityNum = 1
	}
	return opacityNum
}